Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets"
"van trinh cho snippets" » "van thinh cho snippets", "van tinh cho snippets", "dan trinh cho snippets", "van trinh chao snippets", "van trinh co snippets", "van trinh chat snippets"
"locating bug code snippets" » "locating bug core snippets", "locating bung code snippets", "locating bugs code snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("using java code snippets") or ("van trinh cho snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("van trinh cho snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( van trinh cho snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("van trinh cho snippets"))) or ("locating bug code snippets"))*.